For example, a related art discloses a power semiconductor device equipped with power devices, a high voltage-side driver and a low voltage-side driver. Such a power device is composed of high voltage-side power devices and low voltage-side power devices connected in series. The high voltage-side driver drives the high voltage-side power devices, and the low voltage-side driver drives the low voltage-side power devices. The high voltage-side driver has a pulse generator. When the high voltage-side driver receives high voltage-side signals transmitted from an external electric control unit composed of a microcomputer, the pulse generator generates two types of signals, i.e. a turn-on signal and a turn-off signal in a pulse shape on the basis of the received high voltage-side signals (such as pulse width modulation signals (PWM signals).
When a gate terminal of each of level-shift transistors receives the turn-on signal and the turn-off signal transmitted from the pulse generator, a high voltage is supplied to a drain terminal of each of the level-shift transistors, and the drain terminal of each of the level-shift transistors is connected to a set-signal input terminal and a rest-signal input terminal of a flip-flop circuit through an inverter.
An output terminal of the flip-flop circuit is connected to a gate terminal of each of PMOS transistors and NMOS transistors as the high voltage-side drive elements. A drain terminal of each of the PMOS transistors and the NMOS transistors is connected to a gate terminal of the high voltage-side power device.